Evaporative condenser



May 17, 1938. F R ERBACH 2,117,411

EvAPoRATIvE coNDENsER Filed Dec.V 4, 1956 s sheets-sheet 1 May 17, 1938.F. R. ERBACH EVAPORATIVE CONDENSER Filed Dec. 4,- 195e 5 Sheets-Sheet 2WIA IINIM zw@ .JW w f /WV mw mm @n 1 l 1 i j ,ww 6 T l# J L.. uw

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May 17, 1938. F, R, ERBACH 2,117,411

EVAPORATIVE CONDENSERA Filed Dec. 4, 1956 5 Sheets-Sheet 5 niet ay l?,1938 aiu-,4u

EVAPEA CUNDENSER F llt. Erbach, Beloit, Wis., assigner to GeneralReirigeration Corporation, Beloit, Wis., a corporation oi DelawareApplication ember d, 1936;. Serial No. lldtll *i cui. (ci. asv-.svi ulilac invention relates generally to the art of rchieeration with moreparticular reference to improvements in apratus for cooling condensercoils by the evaporation of moisture, thereby' rapa idly removing heatfrom the condenser coils which may have a high temperature refrigerantgas or other high temperature gas orv liquid owing therethrh.

in a. refrigeration machine the hot discharge l@ gas tro the compressormust be cooled in order to condense the refrigerant and return it to thereceiver m a liquid. The heat may be removed by means of air as in anair cooled condenser, by

means ci waterv flowing through a water cooled id condenser in which thewater temperature is raised, or by evaporation of water, in which caseboth air and water are used as the means for removing the heat from thecondenser coils.

object oi the invention is to provide an im- Zo proved evaporativecondenser having increased emciency which is attained by thoroughlymimng o the air and water and properly distributing the mixture over theace of the condenser coils lwhere evaporation takes place.

2e Another object ci the invention is to provide an evaporativecondenser wherein the motor for operating the ian and water pump ismounted vertically above the tank, thereby eliminating pacliing boites,bearings, or ittings below the so water level in the tanh which mightleak or be the cause ci serious trouble.

Another object ot the invention is to provide an evaporative condenservhaving a pump of the simplest rotative cone design in which water enasters at the bottom inlet of the cone and is deilected upwardly until itreaches the mouth of the cone, whereupon it is discharged by centrifugalforce across the air streams entering the ian. y this arrangementthorough mixing oi the air u@ and moisture as it passes into the fan issecured.

Another object of the invention is to provide an proved arrangement of rcondenser coils wherein the high temperature gases are intro' ducedthrough a header at the outside of the 45 condenser coils, which consistof a series ofilat spirals of copper tubing connected in parallel to sinide-header forming the outlet for the condenser. According to theinvention as the spirals progress toward the center of the coilthey havea 5o downward pitch, permitting the condensed refrigerant liquid orother liquid to drain inward toward the outlet header'. The arrangementalso results in accomplishing the counter-flow principle in heatexchange. The hot discharged gas is fed 55. in at the outside of thecondenser and as it proa result oi the evaporation oi water.

grasses toward the center itis cooled. Thus the condenser liquid iscooled to the minimum inlet airtemperature and the outlet discharge airtemperature is raised to the maximum degree pos sible.

The invention is also concerned. with the provision oi an evaporativecondenser wherein the condenser surfaces can be readily cleaned toremove the hard deposits which adhere thereto as Practically 1o allwater is hard and contains minerals which may cause an encrustation overthe surface ci the condenser. The condenser coils of the presentevaporator are mounted in a tank that can be Hooded to submerge thecoils in a cleaning sol5 lution of the proper chemical analysis fordissolving the particular type of mineral deposits left on the coils bythe evaporatlng water. d special K valve is provided by means oi. whichthe water level may be changed from the normal operating 2o level to theHooded level for cleaning purposes and which may be opened for drag thetank after completion of the cleaning process.

With these and various other objects in view, the invention may consistof certain novel iea- 2e tures ci construction and operation, as will bemore fully described and particularly pointed out in the specication,drawings and cl in. appended hereto. s

In the drawings4 which illustrate an embodi- 36 ment of the inventionand wherein like referenceA characters are used to designate lilreparts--V Figure li is an elevational view, parts being shown in section,oi the evaporative condenser embodying the features of the invention;`as

Figure 2 is a top plan view of the evaporativev condenser of Figure lwith the cover plate for the .tank and fan motor removed, and

Figure 3 is an end elevational view oi the evaporator looking toward theleft in Figure 1. 4o

In the embodiment of the invention selected 'for illustration in thedrawings, the operating parts of the present evaporator are supportedupon a table having a top I0 substantially rectangular in plan and whichin turn is supported 45 on any suitable foundation by means oftheuprights Il having circular foot rests I2. Suspended by means ofU-shaped rods I3 from the table top I0 is a cylindrical tank I4 formingthe receiver for the liquid medium after the same has 50 been condensedby the condensing structure to be presently described. 'Iherespectiyeends of l, the rod I3 are secured by `nuts I6 to the .bracketsI6 which are fastened asv by welding to tha-'undersuriace of the-topplate I0.

The top plate I0 comprises the bottom of the tank which is formed by thecylindrical side wall I1 welded to said top plate so as to form a uidtight connection therewith. The top member of the tank comprises aremovable cover I8 having a depending ange I3 adapted vto Viit withinthe cylindrical wall I1 of the tank and thus properly positions thecover thereon. Suitably secured to the exterior orf the cylindrical wallI1 of the tank are upwardly projecting pins 28 adapted to pass throughopenings formed in the cover and receive screws 2i, thereby releasablysecuring the cover in place. Said cover has formed integral therewithupwardly extending lugs 22 which form supports for plate member 23, thesame being releasably secured thereto by the threaded screws 24, therubber inserts 25 being interposed therebetween in order to cushion the-vibrations of the motor 28 supported by said plate member. The rotorshaft v21 of said motor extends centrally through the opening 28 in thecover I8 formed by the downwardly curved Walls 28 and attached.

to the lower end thereofby the connecting webs 38 is a pump tube formedby the inverted cone 3l. Said pump tube carries the centrifugal fandesignated generally in Figure 1 by numeral 32 and which consists of abase member 33 supporting a plurality of radial plates 34.

Located within the tank I1 and positioned substantially concentric withthe centrifugal fan are a plurality of condenser spirals 36 each havingconnection at its outer end to a supply header 31 and connecting at itsinner end to an outlet header 38. Each header extends upwardly throughthe base I0 of the tank and is positioned with respect to the otherheader so as to give each spiral a downward pitch as thespiraiprogresses from the header 31 to the outlet head er 38. Asa result oilin the high temperature Sas flowing through the condenser spirals andthe condensed liquid will drain inward toward the outlet header. 'I'hespaced vertical rods 39 maintain the spiral coilsin proper superimposedrelation. 'I'hree sets of theserods are used, each set being retained inspaced relation by the top member 40 which is heldlagainst the rods bythe screw 4I having threaded connection with cover I8. The header 31 isjoined to a supply pipe 42 by which high temperature refrigerant gas orother high temperature gas or liquid may be delivered to said header andthus to the spiral coils connecting therewith. In

a like manner tlfe outlet header 31 connects with an outlet pipe 43which discharges in to the re'- ceiver I4, the same being connectedthereto by the member 44.

I'he space between the cover I8 and the plate member 23 forms the airinlet for the centrifugal fan, air being drawn through said space andthrough the central opening 28 in saidcover and being delivered therebyto said fan. The duct 45, substantially rectangular in cross section,comprises the air outlet for said tank, said duct having a tangentialconnection therewith, as will be clearly understood! by reference toFigure 2. Water is supplied to said tank for cleaning or 'ilushingpurposes by the water pipe 48 which.

passes throughthe side wall of the duct 45 so as to discharge withinsaid duct, said discharge end of the pipe being suitably secured to thewall f by nuts 41. Joined tov the water main 48 is a valved connection48, regulated by handle 48,

and which lis provided with tubel connecting with a oat operated valve5I, suitably located within said tank. The outlet 52 from said valve,

`like adhering thereto as a result of the evaporation of water by saidcoils. For'this reason the present tank is constructed so that the airinlet and the air outlet will be above the water level in the tankduring the cleaning operation. The flood level of the water isdetermined by the overflow connection 58 joined by pipe 51 to connection58, having valve therein. This last mentioned] connection determines thenormal level of the water within the tank.

During operation of the structure above de` scribed the pump tube 3|will dip into the water in the bottom of the tank since the normal waterlevel, as determined by voutlet 88, will be slightly above the -lowerend of .said pump tube. When the motor 28 is started, causing rotationof the fan, water is caused to ow up the pump tube 3l and to bedischarged radially in a ne spray from the upper end of said pump tube..Ac-`

cordingly, the fine water sprays are directed across the path of the airbeing delivered to the fan. 'Ihe pumping action of the inverted cone 3Iis dependent on skin friction and the centrifugal force of the water onthe interior wall of the inverted cone. The water escapes from the endof said pump tube in a substantially horizontal spray ,and moisturetogether with air is accordingly delivered to the blades of the fan. Thedischarge from the fan-therefore comprises air having moisture uniformlydistributed throughout and which is directed against the said spiralcoils 38 of the condenser. Moisture in finely divided form impinges onthe condenser coils 38 surrounding the fan and as said coils are at ahigh' temperature, dueto the high temperature medium such as refrigerantgas flowing therethrough, evaporation readily takes piace. Theevaporation of the water or moisture by the coils abstracts considerableheat from the medium flowing through the coils: This dissipation of heatby the coils takes place rapidly, thus condensing the medium as the sameprogresses toward the outlet header. The present evaporative condenseroperates at -a high eillciency since the water consumption isv a minimumi'or the quantity ofheat dissipated. 'I'he method of cooling thecondenser coils by the evaporation of moisture delivered to the `coilsuniformly by air streams passing thereover and carrying the moisture insuspension isL more eii'ective and more economical than cooling by airor by water only. -The compressor discharge gases or other gas or liquidis delivered to the condenser through the header 31 located to theoutside of the condenser and therefore said medium must flow inwardlytoward the center ofthe spiral coils. However. the direction of the airand water mixture delivered by the fan is. :lust opposite the sameflowing from the center toward the periphery of the condenser coils.This arrangement results in accomplishing the counter-now principle inheat exchange. As a result the refrigerant gas or other medium iscondensed and is cooledl to theminimum inlet air temperature while/thedischarge air temperature is raised to the maximum degree possible.

Another feature of the present condenser resides in the downward pitchof the spiral coils as they progress toward the outlet header 38.

This facilitates the iiow of the condensed liquid toward the outletheader.

A serious problem in a condenser of the above type is that of cleaningthe evaporating surfaces which become coated with deposits left from thewater evaporated. In the present structure the tank can be flooded tosubmerge the coils in a cleaning solution of the properchemical'analysis to dissolve the particular type of mineral depositleft on the coils by said evaporation. This ilooding of the coils ismade possible by locating the air inlet opening and air dischargeopening above the upper level of the coils. For the cleaning operationthe motor 26 is stopped and valve 60 is 4 closed. Water from `the watermain 46 is then admitted to the tank by opening the valve in said maincontrolled by handle 62. The, water will ll the tank to a leveldetermined by the overflow connection 56. For cleaning the condensercoils whenever the hardness in the water is largely calcium bicarbonatehardness, hydrochloric acid has been found satisfactory. 'I'he properquantity of acid is added to the Waterv in the tank after the coils arecompletely submerged. During the cleaning operation the solution may bestirred occasionally or the process can be speeded up by iiowing a hightemperature medium through the coils in order to heat the solution. Atthe end of the cleaning operation the drain I is opened to completelydrain the solution from the tank.

The invention is not to be limited to or by details of construction ofthe particular embodiment thereof illustrated by` the drawings, asvarious other forms of the device will of course be apparent to thoseskilled in the art without departing from the spirit of the invention orthe scope of the claims. 'A

What is claimed is:

1. In an evaporative condenser, in combination, a tank`providing areservoir for water, a cylindrical fan mounted for rotation on avertical axis and located in the upper end of said tank, means rotatingwith the fan for drawing water from said reservoir and discharging thesame radially from the center of said fan, means located above said fandelivering air thereto, a plurality of condenser -coils encircling saidfan and located in the path of said water and air mixture discharged bysaid fan, and an outlet for said air located above the level of saidcondenser coils, whereby said tank may be substantially filled withwater to submerge the condenser coils in order to clean said coils.

2. In an evaporative condenser, the combination with a tank forming areservoir for water, of a plurality of condenser coils supported withinsaid tank, a motor operated fan positioned centrally of said coils andoperating to discharge a water and air mixture over said coils, and anair supply opening and an air discharge outlet located above the levelof said coils, whereby said tank may be substantially iilled with waterto submerge said coils in order to permit cleaning charge outlet locatedabove the level of said condenser coils, whereby said tank may besubstantially lled with water to submerge said condenser coils for thepurpose of cleaning said coils, and means for completely draining saidtank.

4. In an evaporative condenser, the combination with a tank forming areservoir for water, of a plurality of condenser coils supported withinsaid tank, a motor operated fan positioned centrally of said coils andoperating to discharge a water and an air mixture over said coils, anair supply inlet positioned above said fan, an Aair discharge outletlocated above the level of said condenser coils, whereby said tank mayhe substantially lled with water for submerging said condenser coils, anoverow connection for said tank determining the level of the water whensaid coils are submerged, and means for completely draining said tank.

:FRED R. ERBACH.

